HR: 10:35h
AN: OS22B-02 INVITED [Abstracts]
TI: Mapping Coastal Flood Zones for the National Flood Insurance Program
AU: * Carlton, D
EM: david.carlton@dhs.gov
AF: U.S. Department of Homeland Security, FEMA Region X, 130 228th St. SW, Bothell, WA 98021-9796
United States
AU: Cook, C L
EM: carl.cook@dhs.gov
AF: U.S. Department of Homeland Security, FEMA Region X, 130 228th St. SW, Bothell, WA 98021-9796
United States
AU: Weber, J
EM: joseph.weber@dhs.gov
AF: U.S. Department of Homeland Security, FEMA Region X, 130 228th St. SW, Bothell, WA 98021-9796
United States
AB:
The National Flood Insurance Program (NFIP) was created by Congress in 1968, and significantly amended in 1973 to reduce loss
of life and property caused by flooding, reduce disaster relief costs caused by flooding and make Federally backed flood
insurance available to property owners. These goals were to be achieved by requiring building to be built to resist flood
damages, guide construction away from flood hazards, and transferring the cost of flood losses from taxpayers to
policyholders. Areas subject to flood hazards were defined as those areas that have a probability greater than 1 percent of
being inundated in any given year.
Currently over 19,000 communities participate in the NFIP, many of them coastal communities subject to flooding from tides,
storm surge, waves, or tsunamis. The mapping of coastal hazard areas began in the early 1970's and has been evolving ever
since. At first only high tides and storm surge were considered in determining the hazardous areas. Then, after significant
wave caused storm damage to structures outside of the mapped hazard areas wave hazards were also considered. For many years
FEMA has had Guidelines and Specifications for mapping coastal hazards for the East Coast and the Gulf Coast. In September
of 2003 a study was begun to develop similar Guidelines and Specifications for the Pacific Coast. Draft Guidelines and
Specifications will be delivered to FEMA by September 30, 2004.
During the study tsunamis were identified as a potential source of a 1 percent flood event on the West Coast. To better
understand the analytical results, and develop adequate techniques to estimate the magnitude of a tsunami with a 1 percent
probability of being equaled or exceeded in any year, a pilot study has begun at Seaside Oregon. Both the onshore velocity
and the resulting wave runup are critical functions for FEMA to understand and potentially map. The pilot study is a
cooperative venture between NOAA and USGS that is partially funded by both agencies and by FEMA. The results of the pilot
study will help FEMA determine when tsunamis should be considered in mapping coastal hazards, how to predict their impact,
how they should be mapped and possibly the construction standards for zones mapped as having a 1 percent or greater chance of
suffering a tsunami.
DE: 9355 Pacific Ocean
DE: 4564 Tsunamis and storm surges
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting